The present invention relates to a vehicle steering system for guiding a vehicle in response to the operation of a steering unit such as a steering wheel performed by a driver and more particularly to a vehicle steering system capable of forcible steering in order to avoid danger in accordance with the environmental condition.
Automobiles (vehicles) in recent years are equipped with various kinds of safety devices for reducing driving loads and preventing dangers from happening during the travel of vehicles. In a vehicle disclosed in JP-A-2000-168442, for example, an imaging device covers a rearward imaging visual field and the detection of environmental conditions of one's own vehicle is based on the results of processing the images picked up by the imaging device, whereby the detected results are used to issue or express a predetermined warning.
However, inexperience drivers in particular tend to confine their attention to the forward side. As driving is normally done on any road with other vehicles running both in front and rear and side by side, the drivers are needed to pay attention forward and backward and also sideways. The vehicle disclosed in JP-A-2000-168442 above is designed to prevent dangers from happening when the following vehicle rapidly approaching behind one's own vehicle by informing its driver of environmental conditions in the rear and on both lateral sides of the vehicle, to which sides attention may be hardly directed.
With such an arrangement that a warning is issued or expressed in response to the detection of the environmental conditions as described above, there develops a problem arising from the fact that the proper action of steering for preventing dangers from happening is not taken in response to the detection thereof. In the case of inexperienced drivers in particular, it is even feared that sudden driving operation in response to a warning, for example, wheeling a vehicle almost without thinking may newly cause a danger.
The problem above may be settled by making a warning a voice message on the basis of the detected results of the environmental conditions and providing information on the kinds of environmental conditions such as the approach of the following vehicle and deviation from a vehicle lane including proper driving technique. However, the problem in this case is that the system tends to become complicated because the arrangement above makes it necessary to issue different voice messages depending on the situation by distinguishing among numerous environmental conditions brought about during the travel of one's own vehicle.